Supplementary birth leave: rules applicable to the employer

Verified 03 June 2026 - Entreprendre Public Service / Directorate of Legal and Administrative Information (Prime Minister)

Supplementary birth leave (CSN) is introduced for employees who are parents of a child born or adopted since 1er January 2026 (or of a child born before that date but whose birth was supposed to take place from that date). Each parent can benefit from this leave, for a period of one or two months, in addition to maternity, paternity, foster care or adoption leave. He is compensated by social security.

Supplementary birth leave is in addition to maternity leave, paternity and childcare leave or adoption leave, when the child is completed.

It can be taken by the employee in a 9 months delay from the birth of the child or, in the case of adoptive parents, from the arrival of the child at home.

This period of 9 months may be extended in certain specific cases (long-term maternity leave and hospitalization of the newborn).

FYI  

Supplementary birth leave applies to employees who are parents of children born or whose birth was planned from 1er January 2026, and, in the case of adoption, children who have arrived at home, from 1er January 2026.

If the child was born (or, in the case of adoption, has arrived at home) between 1er January and May 31, 2026, the employee may take additional birth leave within 9 months from 1er July 2026.

In practice, the time taken to take such leave depends on the child's date of birth or arrival at home.

For more details on the applicable deadlines, see this fact sheet on the additional birth leave for an employee.

Deadline

If one of its employees (mother, father or spouse of the child's mother) wishes to take additional birth leave, the employer must be informed at least one month before, by registered letter with acknowledgement of receipt or delivery against receipt.

This period is 15 days if the leave immediately follows paternity leave or adoption leave.

FYI  

Taking into account the obligation for employees to respect a notice period of at least one month, employers can receive the first leave requests from 1er June 2026, for leave from 1er July 2026.

Detail of information

The employer shall be informed of the following:

  • Leave Start Date
  • Duration (1 or 2 months), and if the leave is split or taken in one go (this leave can be split into 2 periods of 1 month).

The employer may not refuse or require postponement of this leave.

Supplementary birth leave is in addition to existing leave (maternity leave, paternity and childcare leave and adoption leave). It does not replace them.

During the additional birth leave the employment contract is suspended.

This suspension has the following consequences:

  • The employee may not engage in any other professional activity during this leave.
  • The employer may not terminate an employee's employment contract during additional birth leave. Only gross negligence or the impossibility of maintaining the contract for any reason other than the birth or arrival of the child could justify the termination of the contract.
  • The duration of the leave shall be deemed to be actual working time for the calculation of the employee's entitlements related to his seniority.

Please note

One early resumption the activity of the employee is possible in the event of the death of the child or a significant decrease in the resources of his household.

As with other reasons for work stoppages, the employer must take two separate and complementary steps:

Net-companies provides a handy sheet to declare additional birth leave in DSN:

Factsheet: Declaring additional birth leave in DSN 

Net-companies-GIP Modernization of social declarations

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